This hand-carved rock crystal ewer, made for the court of the Fatimid rulers of Cairo in the late 10th or early 11th centuries, was mistaken for a 19th century French wine jug earlier this year. (Christie's/Associated Press)

A rare treasure from an ancient Islamic dynasty sold for more than $6 million Cdn at a London auction on Tuesday.

A 1,000-year-old decanter painstakingly hand-carved from a single, flawless piece of crystal sold to an anonymous buyer for about $6.1 million, including the buyer's premium for Christie's auction house.

Earlier this year, an auction house in southwestern England had mistaken the intricately crafted artifact for a mere 19th century French wine pitcher and given it a pre-sale estimate of less than $400.

However, once at auction, the slim-necked, gold-embellished decanter drew the attention of eagle-eyed collectors, who launched a bidding war that eventually drove up the price to approximately $400,000.

After the ewer was correctly identified, however, that sale was annulled.

According to Christie's, the ewer is "one of the rarest and most desirable works of art from the Islamic world."

The rock crystal ewer dates from the late 10th or early 11th century, and is one of only seven similar vessels known to have survived the court of Cairo's Fatimid rulers.

When the dynasty was overthrown, its members were forced to sell their treasures, including the rare, exquisite ewers.

Among the six others known to exist, one is held by London's Victoria and Albert Museum while another is in the collection of the Louvre in Paris.

With files from the Associated Press